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spectroscope to map out the IR-A and UV-A transition

Discussion in 'Feedback/Suggestions' started by shiran, Jul 23, 2017.

  1. drezy

    drezy New Member

    I've got a NIST calibrated UVA meter that went from 0.0 to 0.1 mw/cm2 between 7:20 & 7:30.

    time solar altitude azimuth
    07:20 4.3 75.2
    *Here
    07:30 6.3 76.4

    EDIT:
    Yes, it was that time when the sun goes from reddish to yellowish.
     
    Last edited: Aug 12, 2017
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  2. Sue-UK

    Sue-UK New Member

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  3. drezy

    drezy New Member

    You know you're a Kruse geek when...

    Because people you care about asked a really good question, you're sitting outside at 6AM with a Kiniki on, a big glass of ice water, and a UVA irradiance meter with feet on the plants you know have deeper taproots that you just shared a little of your water with.
     
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  4. shiran

    shiran Curious

    That's absolutely kruse geek .
    Same here waiting for it every morning ...
    This morning was one of the best ones..
    clear sky no clouds...
    Started raising up the mountain in a beautiful red Hypnotic color
    I literally didn't take my eyes off the sun
    It was an amazing transformation
    And i saw all the stages of the changing colors
    I have to say : l love the sun !!!
     
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  5. seanb4

    seanb4 New Member

    According to this graph, UVA appears around about 5 degrees. This makes me think I am missing The VIS + IR bit of the sun as due to terrain, I don't see sun until 35 minutes after rising. I estimate that the sun raises at around 7 degrees an hour....[​IMG]
     
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  6. Sue-UK

    Sue-UK New Member

    If its light there's photons, and you don't need a lot for signalling (think how few blue ones can shut off melatonin at night ....). As the sky colour changes the ratio and dominance of different colours changes, and the brain also registers the increasing crescendo. Many species live on terrain that blocks the direct rays or the camera image of the rising sun. I see it that the photons are not the sun, but they are of the sun, information carriers, and that I am still bathing in the light, and harvesting, even if I can't see the source. :)

    PS thanks for the pic ... It seems to suggest (from the pic I posted earlier) that when yellow becomes the dominant visible frequency in the morning, that UVA is kicking in. :)
     
    Last edited: Aug 16, 2017
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  7. shiran

    shiran Curious

    Jack mentions the importance of the transition in the morning .
    If we are anyway out there every morning, I'm curious why is it so important for you guys to know exactly when the transition is happening ?
    People who have limited time in the morning for example..
    I would like to be more specific in my recommendation to people regarding the morning exposure..

    Another thing I was thinking about was..
    If we sleep in a dark room no light gets in ( not like in nature)
    how does the body senses it's morning and wakes up naturally ?
     
  8. Sue-UK

    Sue-UK New Member

    If I understand it right, the blue and red in the early visible light switches the pituitary on, stimulating releasing pituitary hormones. The UV coming in switches the hormones off. So if you go straight out to UV it can affect hormone release. If you see the VIS but miss the UVA transition, you could leave the pituitary hormones switched on when they should be off (or at least the seasonal volume turned down IYKWIM). Also the early morning light and a period of UVA preconditions the skin for UVB. IIRC the first bit of UVA may cause DNA damage, but then it stimulates DNA repair, so the longer I stay out in the morning, the better overall response.

    Because of animals underground, hibernation etc, I believe we are also heavily influenced by the earth's rotation, as well as the light cues from the environment that fine tunes us to day length and season. If I look at a picture of the magnetosphere, and think of my location entering the magnetotail at night, (change....), in the middle of the magnetotail (change) and then emerging in the morning, (change) I think of it as the darker the room is, the more sensitive I am to that part of the biological magnetic field rhythm of the earth at night, that it improves my sleep biological rhythms and I wake up at the right time without needing a light signal. Then my aim is to "fine tune" it with the natural frequencies of light during the day, turning things on and off, or turning the volume up and down at the right time, with hormones fluctuating, in line with the season and latitude. :)
     
    Last edited: Aug 16, 2017
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  9. shiran

    shiran Curious

    That's interesting , I would love a blue light - sun - boot camp to learn more
     
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  10. Inger

    Inger Silver

    I always sleep with wide open window, my bed is right at the window... and no curtains, so I wake up from the light shining on my face....
    Funnily I can sleep past sunrise tho, when sun rises very early I can still sleep until 7 AM, that is when i mostly wake up.. My eyes face east-south when I wake up, but the light still come into my room and I love it :). I do not like curtains and closed windows at all!
    But I get no fake light at all into my bedroom window.. outside is only green and the heaven...
     
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  11. Ted

    Ted New Member

    Great explanation.
     
  12. brent-next

    brent-next Gold

    That looks like a lot more fun than my Sun Friend UV A+B watch. I want one! how much and when can I get one? Please send me a private message or post the details here.
     
  13. drezy

    drezy New Member

    Brent, I loved your questions to doc in the recent Q&A concerning Cuba. Your curiosity may have actually opened up a future residence for my wife and I and I'm grateful that you got doc to dump the info.

    Short story:
    We are making changes to the unit to make it more sensible. Even @kvond did not receive her Beta yet. Sorry @kvond I hope you are getting your morning light regardless

    Longer story:

    The bright OLED display really kinda sucked from a mitochondriac perspective. We've switched to a LCD screen. It does not emit any light since there is no point for a light sensor to emit it's own light. If you're using it in the dark then you need a little psychological counseling anyway...

    Also we found a good LiPo rechargeable battery to slap in there to recharge over micro usb.

    Reviewing the sensor manufacturer's data the UV-B is really stretching it:
    • UV-A sensor peak 365nm. The bandwidth (λ0.5) of the UVA channel is within a range of about 350 nm to 375 nm (ok I'm cool enough with that)
    • UV-B sensor peak 330nm. The bandwidth (λ0.5) of this UVB peak is in a range of about 315 nm to 340 nm. (That's kinda stretching it)
    We don't want to BS people. The 330nm detection(spurious as it is) does actually help with UVindex erythemal calculations. So I think we're settling on UV-A+ UV-A accumulation(J/cm2) + UVi on the display at this point. I'll hit you with a PM. The good news for you is that a 12 yo performs the labor here. Child labor is cheap, but it's not just one way. I'm building my son up for kick-ass science projects through his educational period.

    I literally shoveled horse crap for a few bucks when I was his age. If he puts together UV-A + UVi monitoring units for a few bucks then it seems like a fair generational improvement to me...
     
  14. Jack Kruse

    Jack Kruse Administrator

    August webinar is all on Cuba FYI
     
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  15. brent-next

    brent-next Gold

    Yes, Dr. Kruse gave some very useful information on Cuba in the August 2017 webinar. Members who haven't listened to it yet should do so, and non-members should consider signing up.

    I asked a professional guide to Cuba (from Norway) what she thought about pollution in Cuba. She confirmed that downtown Havana is very polluted, with the outskirts of Havana being slightly less polluted.

    She liked the resort towns of Cienfuegos and Trinidad and had this to say about levels of pollution away from Havana.

    "Apart from Havana there is very little traffic in Cuba as very few people own their own car or can afford to pay for fuel."

    It should be easy to find Canadians who have spent a lot of time in Cuba and can tell you more about it. Canadian travel agencies might also be a good source of up to date travel information.
     
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  16. Lahelada

    Lahelada New Member

    How is the spectrometer going @drezy ?

    I was just checking that my internal clock has adjusted to summertime (it hasn't ) and found out my UVA window. I looked at your figures for when UVA showed up for you in your post (https://forum.jackkruse.com/index.p...-and-uv-a-transition.19869/page-2#post-221513 )when you measured the jump from ) to o.1 % UV. Assuming you measured in Texas that would mean that there is no UV in summer for around the first hour after sunrise. However...

    Sean's graph however say 5 degree elevation. That would mean though that your actual window would end at 6.25 not 7.30 ,unless my calculator does not account for Daylight savings time. Or maybe your reading was not adjusted to daylight savings time ?

    This is the calculator I use.
    https://www.esrl.noaa.gov/gmd/grad/solcalc/azel.html
     
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  17. philip malone

    philip malone Silver

    Sounds quite cool : )
     
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  18. drezy

    drezy New Member


    Uh oh, I'm getting called out on this one. This side project has been a dream project to work on with my son. It's also become a bit of an engineer-gone-wild (not as exciting as girls gone wild BTW ) venture (imagine a pig discovering a cool patch of mud on a summer day).

    The hardware designer on this project is pretty caught up. It's his software engineer that is behind a bit(though rumor has it he's tall and handsome FYI).

    I'll break it down several month's design changes in pictures:
    spectrums.png

    On the left is the spectral Irradiance responsivity of Rev 0.1. On the right is Rev 0.4 (worked on over the last 6 months). Note a bit of a spectra difference (2 to 14).

    Our design goal when viewing simple color temperature meters (lumu - $269) was to come in lower than $200 as well as add fine resolution UV & IR detection. Would aspiring film students appreciate a cheaper light meter? I've got feelers out for this currently as well as a dialog with a film equipment rental house. Could many small film producers bankroll some mitochondriac economies of scale savings... Maybe, we'll see.

    We bought this UV meter ($250) 4 months ago. Did we buy it just to use it personally? Nope. Can we match the results for less on a consumer level with the rev 1.0 sensor? Yep.

    Note that from the image on the left(0.1) to the image on the right(0.4) it goes from 2 spectra to 14 spectra. The design goal is that if you have consumer level dollars but are interested in the spectrum from 300-900, like only people here would be, then there should be a solution for you.

    We feel strongly in this house about people seeing their environment. We want to become a solution to part of that.
     
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  19. WalterNL

    WalterNL New Member

    That is simply awesome @drezy . Funny how it links up with film producers, engineering students may also interested in portable light meters. Gotta check the rays before going outside. :cool:
     
  20. drezy

    drezy New Member

    Nah, that's just hardware and software co-development when you put a little skin in the game. Following along here will make you be a better you.

    As far as you are concerned you should suspect I'm full of sh*t. I work even better under those conditions.

    After doing cold tubs for nearly 10 months my ideas and designs come on in fast and furious upon waking. They eat my previous ideas and designs for breakfast and leave them in the dust. Senors are one thing, applications are another...

    So much is within reach. My son gets the fun hardware design projects... I'm trying my hand at an opto-decoupled usb/keyboard port. I don't know about anyone else but my laptop blows crap emf when it's plugged in. I'm designing this for myself, if others want in that's cool too. I'm done sitting on the sidelines.
     
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